Method of making trussed structures.



A, J. BATES.

METHOD OF MAKING TRUSSED STRUCTURES.

APPLIOATION FILED 32m. 23, 1910.

Lwsflga, iatnted 00$. 17, 1911 3 SHEETS-SHEET l A; J. BATES.

METHOD OF MAKING TRUSSED STRUCTURES. APPLICATION FILED SEPT. 23, 1910.

1,@05,9g5, Patented 001;. 17, 1911. v I SSHBETSVSHEB'I 2.

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h M W W afi jus A. J. BATES METHOD OF MAKING TRUSSED STRUCTURE.

APPLICATION FILED SEPT, 23, 1910.

Patented Got. 1'7, 1911.

ALBERT J. BATES, OF CHICAGO, ILLINOIS.

METHOD OF MAKING TBUSSED STRUCTURES.

oosocs.

Specification of Letters Patent.

original application filed April 18, 1910, Serial No. 556,221.

Patented Oct. 17, 191i. Divided and this application .flled September23, 1910. Serial No. 583.394.

To (all whom it may ronccrn: V

llc 1L known thut l, .zlrmnrr J. .liA'lES, a

citizen. of the United States, residing at Chi- Trusscd Structures, oiwhich the following is a. specification.

This is u division of my application Se.- riul l lo. :36.223. filedApril 18, 1910. and the invention relates to the formation of anintegral metallic structure having longitudinally extending side membersspaced apart and connected at, intervals throughout their length bytruss members which are preforubly angulzirly disposed to the sidemon'ibcrs.

So for as I am aware, crossed structures heretofore employed in thoconstruction of buildings. lwidges. elevated railways and other me a.work. Have been built. up of longitudinal side members connectedtogether by cross pieces riveted or bolted thereto.

My invention aims to obviate the necessity of building up st'ructilncsof this kind from scpzirutc parts by converting a. solid bar or strip ofmetal into a skeleton. structure having all of its parts embodied in anintegral formation of the same or substci'rtiully the some length as theoriginal bar or strip. thus producing trussod structure with a. certaininherent elasticity and consisting essentially of longitudinal sideillcn'lbers and transverse. truss members uugulurly disposed with relction to the side. members to :torm a plurality of adjacenttriangular-shaped openings'in the. strucrure. In the formation of thestrucc the side irlembcrs remain substantially unciungod in shape,lcngth and thickness,

but the truss members are stretched. lengthwise. and more or lessreduced in cross i'ziou. this method I am enabled to produos a'struclmrc much stronger than the built-up structures heretofore employedand time from the wcaluiesscs at. the joints of the ports in the. old.structures; and, furthermore, my ii'itcgrsl structure is much more rigidand durable than a built'up structure, ill Which thcrc the constantliability of bolts or rivets working loose or being sheared oil.

Another object of my invcnlzion is the pro dilution by a simple andinexpensive method of a structure in which the strains and stresses aredistributed evenly throughout its length, which desideratum ispractically impossible in builtup structures because of the inevitableinaccuracies which creep into an attempt to make a large number ofpieces of exactly the some. length on. to drill or punch :1 large numberof holes which shall be spaced exactly the same distance apart.

My invention also aims to producc a structure which shall be light inweight, which can be manufactured at low cost, and which is capable ofa. variety of uses to which a built-up structure could not besuccessfully adopted.

Additional aims and objects of my invention. will be apparentto thoseskilled in the art as it becomes better understood by reference to thefollowing description in connection with the accompanying drawingsillustrating the invention.

Referring to'the. drawings, Figure l is a. plan of a bar or strip ofmetal from which my improved structure is made. F ig. 2 is a i plan ofthis bar after grooving and slittingopcrullons have. been completed.Fig. 3 is a plan showing the side members of the bar partiallyseparated. Fig. 4 shows side sections separated to produce a. trusscdstrum turc of maximum strength. Fig. 5 is a section on the line of F i4-. Fig. 6 is a. section on the line G(3 of Fig. 2. Figs. 7 to 10 areviews similar to Fig. 6 showing other forms of bar. Fig. 11 is a Viewsimilar to Fig. 2, but having slits therein of graduated lengths toproduce a. tapering structure. F ig. 1.2 shows the resulting structureafter the side members of Fig. 11 have been separated. Fig. '13 is aside View or" on I-beam slittcd according to my invcntion. Fig. 14 showsa i method of connecting two of my improved crossed structures; Fig. 15is a section on the. line 15-45, of F ig. 14. Fig. 16 is a section onthe line 16-16 of Fig. 13. Fig. 17 shows a. tool constructed to engagewith the side members of a. slitted bar for the purpose of separatingthem. Fig. 18 shows my invention employed as a. fence post.

In practicing my invention I provide a bar or strip or beam 17 which maybe made in nisny different forms ill CI'OSS-S9ftion. lnllig. 6 the baris provided with grooves or longitudinal depressions 18 near edge whichform grip surfaces so that tllc bar can be firmly grasped by a tool. ormachine for the purpose of separating the side mcmbcrs. as will be laterdescribed. The grip surfaces may be otherwise proother and in duce'tl,by the flanges 19, (Fig. 7), the grooves 20, (Fig. 8), the beads 21,(Fig. 9). the ribs 22 (Fig. 10), or the side members may be roughened toinsure proper engagement by the tool. Instead of forming these grippingsurfaces on the bar. the drawing or stretching means may be providedwith suitable ripping surfaces to make locking engagement with the bar.

The bar, with or Without the gripping surfaces, is provided with a.plurality of slits 23 extending longitudinally throughout its length andin staggered relation to each two series. These slits, as shown in Fig.2, are of substantially equal length, the ends of the slits beingseparated by'an integral tie portion 2% affording sufficicnt strci'igth.to prevent fracture during the separating or drawing operation. Theuncut tie portions 2% between the slits in each series are preferablydisposed substan tially opposite the center of the slits in the otherseries, and each series of slits is located substantially equidistantfrom the edges oi the bar and from each other. thus dividing the barinto two longitudinal side members 26, and an intermediate member 27.The slits may be produced by any suitable cutting implement With the barin either heated or cold condition, as may be found desirable.

After the slitting operation, the side members of the bar are graspedthroughouttheir length, or at such points as may be found practical andsutllcient, by a suitable stretchingtool or implement. Any preferredtype of stretching or drawing device may be employed, one type beingshown in Fig. 17 for the purpose oi. illustration merely. T he deviceshown comprises jaws 28 adapted to engage the previously describedgripping surfaces on the side members. Suitable means are employed forpulling the jaws to separate the side members and to stretch or elongatethe sections 529 of the interme diate member of the bar into a sinuousform, as shown in 3, Without increasing or decreasing the length of theside members. The pulling or stretching operation is materiallyfacilitated by heating the bar. and in heavy work the heating oi the baris practically necessary The structure thus produced and as shown inFig. 3 may be employed for numerous purposes, but the form which givesthe maximum strength and eiliciency is disclosed in Fig. 4:, wherein theside members 25 and 26 have been separated until the sections 30 of theintermediate member 27 connecting the tie portions 2%, are straight anddisposed at practically an angle of with the side members. In thusforming the structure the side i'ucmbers are neither changed in lengthnor in thickness, and they are trussctfl and "strengthened by theangularly disposed sections of the intermediate member. The side membersand the elongated sections of the intermediate member form an integralstructure having a plurality of adjacent triangular openings, the sidesof these triangles being formed by the sections and the bases thereof bythe side members. The triangles are arranged With their basesalternating between the side members.

In the structure shown in Figs. 1 to S, inclusive. the slits in the barhave been made of uniform length and the side members hare been drawnapart and maintained in substantial parallelism. If it is desired toproduce a tapering trussed structure, such is disclosed in Fig. 12, theslits 31 are grad uated in length from one end of the bar 32 to theother (Fig. 11). When the stretclr ing operation is performed the longerlits at one end or". the bar will permit the side members 3 3 and 3% tobe separated farther than will the shorter slits near the other end ofthe bar. This structure, shown in Fig. 12, is particularly adapted foruse in aerial structures. such as towers. etc, and as telegraph,telephone or power poles.

In Figs. 13 and 16, I have shown an I-beam slitted for stretching toform a trussed structure adapted for use in building construction, asshown in Figs. 14: and 15. In the latter figures there is shown a girder36 and an uprigh 37. the connection being made by suitable a ag le-bars3S and rivets 39 such as are ordinarily employed in constructions ofthis kind. It will be obvious that a building frame constructed as shownin Fig. 1d may be made much lighter and stronger than a frame fabricatedof the same material in built-up form. A frame of this kind alsoparticularly adapted for. use. in concrete constructions, the concreteuniting with the open Work of the structure to form a firm andsubstantial mechanical bond. I

My inventioii' may also be employed as a. fence post, as shown in Fig.18, wherein the lowerend of the post It!) is embedded and rigidly heldin concrete ell or other suitable material. The Wires 4:2 oi an ordinaryWire fence may be attached to the post by clips 43 or other preferredmeans. A post thus constructed is strong and durable, and enters thegreatest resistance along aline transverse to the direction of the Wiresof the fence. This is a mostusetul and ellicient type of post since thestrain upon the fence is usually exerted against the side thereof whichwill be resisted by the post made as herein described and set as shownin Fig. 18.

It will be obvious from the foregoing description that the structuresproduced by my iiu'ention, as above described, are capable of a varietyof uses both in structural Work and in reinforced concrete work,Furthermore hitching posts,

heretofore employed.

they may be employed in lighter constructions such as telephonepolesorfence posts, etc., and in fact constitute a very cheap andeflicient substitute for either the built-up or solid constructions Thisinvention has the additional advantage that the resultant structure isof the same length as the original bar from which it is madeand the sidemembers are of their original length and cross section, the stretchingtaking place only in the diagonal members bet'ween theside members. Thusmy novel method provides for changing a bar or strip orhbam into askeleton form with the parts integrally connected and disposed in a'manner to provide maximum strength,

rigidity and eiiiciency.

While I have shown and described several forms of structures produced inaccordance with my invention, it will be apparent that these forms areselected for the purposes of illustration merely and that many otherforms may be produced if desired.

What I claim and desire to secure by Letters Patent is:

l. The method of making a trussed metal structure from a single piece ofductile metal, such as a bar, which consists in forming a series ofslits intermediate of and sub stantially parallel to the marginalportions of the bar, and then separating the unsevcred side memberswithout substantially changing their length, and stretching theintermediate members thereby increasing their length and producing anangular relation thereof with respect to the side members.

2. The method of making a truss-ed metal structure which consists informing intermediate the marginal portions of a bar or 4 blank a seriesof slits substantially parallel to said marginal portions and instaggered relation to each other, and then separating the marginalportions without material elongation and stretching the portions betweenthe slits thereby elongating them-and producing an angular relation ofthe elongated members with reference to the marginal members and withreference to each other.

3. The method of making a trussed metal structure from a bar havingmarginal flanges which consists in forming in the web portion of saidbar a series of slits substantially parallel to the margins andstaggered with relation to each other and then separating the marginalportions in. the plane of the web thereby elongating the portions of themetal between the slits without substantial elongation of the marginalmembers or lateral distortion of any ofsaid members.

4. The method of making a trussed metal structure from a single piece ofductile metal which consists in slitting the metal intermediate its sidemargins, the slits being substantially parallel to said margins and instaggered relation to each other, and then while the metal is hotlaterally separating the side margins without substantially changingtheir length while stretching the metal between the slits, therebyproducing a "zig-zag relation of the intermediate portions with relationto each other and t0 the side A. J. BATES.

margins.

Witnesses WM. 0. BELT,

M. A. KInDxE.

